A tornado, also called twister or cyclone, is a violent rotating column of air extending between the Earth’s surface and the base of a thunderstorm.
This vortex of wind, usually funnel-shaped, can be very destructive.
It can destroy large buildings, uproot trees, drive sticks into trees and hurl cars hundreds of yards away.
But in this experiment, we will make a water tornado safely at home.
Let’s see how a rotating vortex is formed.
What you need
- a tall glass or jar (lid is good but optional)
- liquid dish soap
- a stirrer (if there is no lid, you can use pencil, chopstick, straw or an actual stirrer to stir)
- Fill the glass with three quarters of water.
- Put a few drops of dish soap into the water.
- With one hand holding the glass, use the other hand to stir the water quickly in circular motion until a vortex or column of spinning bubbles is formed.
- If you prefer to use a lid, cover the jar tightly and rotate the jar in circles using your wrist.
- Then remove the stirrer, or put down the jar, and observe.
When you stir or spin the water, a vortex is created in the center, similar to the vortex in tornadoes.
In a vortex, the water swirling on the outside has to move faster than the water on the inside to keep up.
This is why in a hurricane, strong winds are felt far away from the center but the center itself (eye) is calm.
Here is a video explaining what we do know about tornadoes.